Lockfile action failed to resolve environment

[rcomer]

📰 Custom Issue

👀 https://github.com/SciTools/iris/actions/runs/3972226328/jobs/6809909691#step:3:1104

[trexfeathers]

Might be worth running in a few more days in case a fix is on its way.

[trexfeathers]

Another possible thing to try would be to use a vanilla Mamba install instead of our current workflow (which was necessary at the time, but don't think that's still true).

        run: |
          source $CONDA/bin/activate base
          conda install -y -c conda-forge conda-libmamba-solver conda-lock libarchive=3.5.2=h5de8990_0
      - name: generate lockfile
        env:
          CONDA_EXPERIMENTAL_SOLVER: libmamba
        run: |
          $CONDA/bin/conda-lock lock -k explicit -p linux-64 -f requirements/ci/${{matrix.python}}.yml
          mv conda-linux-64.lock ${{matrix.python}}-linux-64.lock

[rcomer]

#5163 👀

[trexfeathers]

The failure was previously during updating the base environment in the workflow - resolution failed - so I assume that a new package release has made enabled environment resolution where it wasn't possible before.